Find my old posts

Riksbanken moves close to the ZLB – Now it is time to give Bennett McCallum a call

In a very surprising move the Swedish Riksbank this morning cut its key policy rate by 50bp to 0.25%. It was about time! The Riksbank has for a very long time undershot its 2% inflation target and inflation expectations have consistently been below 2% for a long time as well.

The interesting question now is what is next? The Riksbank is now very close to the Zero Lower Bound and with inflation still way below the inflation target one could argue that even more easing is needed.

I have earlier addressed how to conduct monetary policy at the ZLB for small-open economies like Sweden. Traditional quantitative easing obviously is an option, but it is also possible to get some inspiration from the works of such great economists as Lars E. O. Svensson or Bennett McCallum.

Market Monetarists – like traditional monetarists – of course long have argued that “interest rate targeting” is a terribly bad monetary instrument, but it nonetheless remains the preferred policy instrument of most central banks in the world. Scott Sumner has suggested that central banks instead should use NGDP futures in the conduct of monetary policy and I have in numerous blog posts suggested that central banks in small open economies instead of interest rates could use the currency rate as a policy instrument (not as a target!). See for example my recent post on Singapore’s monetary policy regime.

Bennett McCallum has greatly influenced my thinking on monetary policy and particularly my thinking on using the exchange rate as a policy instrument and I would certainly suggest that policy makers should take a look at especially McCallum’s research on the conduct of monetary policy when interest rates are close to the “zero lower bound”.

…What McCallum suggests is basically that central banks should continue to use interest rates as the key policy instruments, but also that the central bank should announce that if interest rates needs to be lowered below zero then it will automatically switch to a Singaporean style regime, where the central bank will communicate monetary easing and tightening by announcing appreciating/depreciating paths for the country’s exchange rate.

McCallum terms this rule the MC rule. The reason McCallum uses this term is obviously the resemblance of his rule to a Monetary Conditions Index, where monetary conditions are expressed as an index of interest rates and the exchange rate. The thinking behind McCallum’s MC rule, however, is very different from a traditional Monetary Conditions index.

McCallum basically express MC in the following way:

(1) MC=(1-Θ)R+Θ(-Δs)

Where R is the central bank’s key policy rate and Δs is the change in the nominal exchange rate over a certain period. A positive (negative) value for Δs means a depreciation (an appreciation) of the country’s currency. Θ is a weight between 0 and 1.

Hence, the monetary policy instrument is expressed as a weighted average of the key policy rate and the change in the nominal exchange.

It is easy to see that if interest rates hits zero (R=0) then monetary policy will only be expressed as changes in the exchange rate MC=Θ(-Δs).

While McCallum formulate the MC as a linear combination of interest rates and the exchange rate we could also formulate it as a digital rule where the central bank switches between using interest rates and exchange rates dependent on the level of interest rates so that when interest rates are at “normal” levels (well above zero) monetary policy will be communicated in terms if interest rates changes, but when we get near zero the central bank will announce that it will switch to communicating in changes in the nominal exchange rate.

It should be noted that the purpose of the rule is not to improve “competitiveness”, but rather to expand the money base via buying foreign currency to achieve a certain nominal target such as an inflation target or an NGDP level target…

…The point is that monetary policy is far from impotent. There might be a Zero Lower Bound, but there is no liquidity trap. In the monetary policy debate the two are mistakenly often believed to be the same thing. As McCallum expresses it:

“It would be better, I suggest, to use the term “zero lower bound situation,” rather than “liquidity trap,” since the latter seems to imply a priori that there is no available mechanism for generating monetary policy stimulus”

…So central banks are far from “out of ammunition” when they hit the zero lower bound and as McCallum demonstrates the central bank can just switch to managing the exchange rates when that happens. In the “real world” the central banks could of course announce they will be using a MC style instrument to communicate monetary policy. However, this would mean that central banks would have to change their present operational framework and the experience over the past four years have clearly demonstrated that most central banks around the world have a very hard time changing bad habits even when the consequence of this conservatism is stagnation, deflationary pressures, debt crisis and financial distress.

I would therefore suggest a less radical idea, but nonetheless an idea that essentially would be the same as the MC rule. My suggestion would be that for example the Swedish Riksbank … should continue to communicate monetary policy in terms of changes in the interest rates, but also announce that if interest rates where to drop below for example 1% then the central bank would switch to communicating monetary policy changes in terms of projected changes in the exchange rate in the exact same fashion as the Monetary Authorities are doing it in Singapore.

…Imagine for example that the US had had such a rule in place in 2008. As the initial shock hit the Federal Reserve was able to cut rates but as fed funds rates came closer to zero the investors realized that there was an operational (!) limit to the amount of monetary easing the fed could do and the dollar then started to strengthen dramatically. However, had the fed had in place a rule that would have led to an “automatic” switch to a Singapore style policy as interest rates dropped close to zero then the markets would have realized that in advance and there wouldn’t had been any market fears that the Fed would not ease monetary policy further. As a consequence the massive strengthening of the dollar we saw would very likely have been avoided and there would probably never had been a Great Recession.

The problem was not that the fed was not willing to ease monetary policy, but that it operationally was unable to do so initially. Tragically Al Broaddus president of the Richmond Federal Reserve already back in 2003 (See Bob Hetzel’s “Great Recession – Market Failure or Policy Failure?” page 301) had suggested the Federal Reserve should pre-announce what policy instrument(s) should be used in the event that interest rates hit zero. The suggestion tragically was ignored and we now know the consequence of this blunder.

The Swedish Riksbank…can.. avoid repeating the fed’s blunder by already today announcing a MC style. That would lead to an “automatic prevention of the liquidity trap”.

That is it – now back to writing on the Polish central bank’s failure to do the right thing at it’s rate decision yesterday.